174 BEACH GRASS 



winter. A further and more interesting conse- 

 quence resulted. The summer before there had 

 been for the first time a considerable invasion of 

 gypsy caterpillars into my forest, although I had 

 creosoted as many of the egg clusters as could be 

 found the previous winter. At every week-end 

 of the first winter that the little band of chick- 

 adees remained continually at the farm, they were 

 to be seen not only at my feeding shelf but also 

 in the forest, and the egg clusters seemed to be 

 disappearing. No creosote was used and at 

 the end of the winter the egg clusters were gone. 

 I have seen chickadees eating these eggs, and I 

 believe my riddance of these pests was due to 

 them, for, although the forest has never been 

 sprayed and the gypsy eggs have only once been 

 creosoted, the forest has been practically free 

 from this destructive worm. I regard this as an 

 object lesson in the value of birds in keeping down 

 insect pests. To obtain the best results it may 

 be necessary to spray the fruit-trees and some- 

 times other trees to save them, but, in so doing, 

 one loses to a large extent the beneficial work of 

 the birds. Moreover, there is strong evidence 



